Rapid connection couplings for transferring gaseous and/or liquid fluids are known. Examples of such rapid connection couplings are shown and described in U.S. Pat. Nos. 5,927,683 and 5,575,510 and in EP-A 0 340 879 and WO-A 93/20378.
The known rapid connection couplings have a number of disadvantages making them unsuitable for use in refilling a high-pressure, mobile container (such as a gas cylinder) with oxygen in a home environment. The disadvantages of known rapid connection couplings include at least one or more of the following: (i) being relatively complicated to use, making them more suitable for use by a suitably trained cylinder refilling technician, (ii) allowing an unacceptably large amount of high-pressure gas to escape when the coupling is disengaged from a mating fitting affixed to the cylinder, creating an unacceptably loud sound, and possibly causing the fitting and cylinder to forcibly separate from the rapid connection coupling, creating the risk of a projectile hazard, and (iii) having a relatively high parts-count and an a correspondingly high relative cost to manufacture.
There is a need, therefore, for an improved rapid connection coupling for transferring gaseous and/or liquid fluids suitable for untrained users, especially for refilling a mobile container (such as a gas cylinder) with oxygen in a home environment.